Internet access is becoming ubiquitous and the means by which the access is obtained varies widely. For example, the internet access may be through a Digital Subscriber Line (DSL), a cable modem, a fiber optic network, a wireless communication network, etc. When the internet service provides high data rates it is often referred to as broadband internet service. Broadband internet service is generally understood to be a service that is always on and offers data rates on the order of mega-bits per second for both download and upload.
A client device as defined in the present disclosure is a device that may access the internet from one or more of the sources from which the internet service may be available. Such client devices may include conventional devices such as a smartphone, a tablet, a feature-phone, a laptop or a desktop personal computer, etc. Other client devices may include devices that are embedded within devices that perform other functions such as an entertainment system in a home or in an automobile, a home appliance such as a refrigerator or washer/dryer, a wristwatch with a heart rate monitor, a medical device such as a blood pressure meter or insulin sensor, a utility meter, a gaming console, a camera, a navigation device, industrial equipment, etc. These types of devices are collectively referred to herein as machine type client devices.
These diverse types of client devices may access the internet service directly through one of the sources of primary internet access mentioned earlier. Alternatively, the client devices may access the internet through a local network that performs distribution of the primary internet access to the users localized in a given area. Examples of such local networks include Local Area Network (LAN) using Ethernet, Wireless LAN (WLAN) commonly known as Wi-Fi, or some other local area networking schemes. When a client device is in the proximity of a location where such a LAN or WLAN access is available, it may access the internet using the LAN or WLAN. FIG. 1 illustrates an example scenario of client devices accessing internet over a WLAN network, which is connected to a traditional wire-line internet service such as DSL or cable modem. The local area where WLAN service is available is often referred to as Hotspot. The device that offers the WLAN service in a given local area is referred to as an Access Point (AP). In the present disclosure, the terms Hotspot AP, WLAN AP, or Hotspot are used interchangeably to refer to the device that offers the WLAN service in a given local area.
A Hotspot AP may be connected to DSL or cable modem through any of the standardized interfaces such as Universal Serial Bus (USB), Ethernet, or proprietary interfaces. In some cases, the DSL or cable modem and the Hotspot AP may be part of a single physical device. In such cases the interface between the DSL or cable modem and AP may use Secure Digital Input Output (SDIO) or other suitable interface.
Client devices may also obtain internet access over mobile wireless networks. These mobile wireless networks are often referred to as Wireless Wide Area Network (WWAN). The internet service offered by such networks is often referred to as mobile broadband internet or Mobile Broadband (MB) and the mobile wireless networks are often referred to as mobile broadband networks. The terms WWAN and MB are used interchangeably herein.
As the variety of client devices has increased and the demand for MB access has increased, a device known as a mobile Hotspot is commonly used. A mobile Hotspot device includes both a modem for MB access and a WLAN AP (Hotspot AP) to distribute the internet to local client devices. FIG. 2 illustrates the block diagram of an example mobile Hotspot device. As shown in FIG. 2, for the chosen example, the WWAN modem and the WLAN AP may be connected to each other via one of the standard interfaces used in the industry such as USB, SDIO, or proprietary interfaces. The WWAN modem and the WLAN AP may be controlled by the Mobile Hotspot Controller which may be a separate processor or hardware logic circuitry. Alternatively, the Mobile Hotspot Controller may be implemented as software and may run on the Central Processing Unit (CPU) or other processor of the WWAN modem or WLAN AP. The hardware and software comprising the WWAN modem may be referred to as the WWAN modem subsystem. Similarly, the hardware and software comprising the WLAN AP may be referred to as the WLAN AP subsystem. In another mobile Hotspot example, the WWAN modem and the WLAN AP may be a single Integrated Circuit (IC) as shown in FIG. 3. The WWAN modem and the WLAN AP may be controlled by the Mobile Hotspot Controller which may be running in a single CPU common to all. The Mobile Hotspot Controller may be implemented as a processor or a processing logic circuitry or combinations of the two. In yet another example, a mobile Hotspot comprising WWAN modem, WLAN AP, Bluetooth™ Master Controller, and USB Host controller is illustrated in FIG. 4. In this example, the four subsystems may be controlled by the Mobile Hotspot Controller which may be running in a separate CPU with its associated memory.
Some mobile Hotspot devices may serve as a single function device, i.e., they only perform the mobile Hotspot function. Such mobile Hotspot devices may take many different form factors such as a mobile Hotspot integrated into an automobile, a standalone device that can be carried around with or without a battery, integrated into an accessory device for a tablet, a standalone device that can be powered by a wall outlet, etc.
Some client devices have multiple capabilities and being a Hotspot is one of the capabilities. For example, a smartphone may have a mobile broadband modem that may be used to get mobile internet service directly from the mobile broadband network as illustrated in FIG. 5. The flow of internet data is as shown in FIG. 5 from the mobile broadband modem to the application processor that processes the download and upload data and interacts with the user via the display and other elements of the user interface such as audio, vibration, etc. The smartphone may also have a WLAN modem to access internet service over a WLAN AP. When it is in the vicinity of a WLAN AP, it may use internet service from the WLAN AP as illustrated in FIG. 1. In another smartphone example, the mobile broadband modem, the WLAN AP and the Application Processor may be integrated into a single Integrated Circuit (IC) as shown in FIG. 6.
A smartphone may also serve as a mobile Hotspot to provide internet service over WLAN to other client devices in its vicinity. FIG. 7 illustrates an example scenario where the smartphone serves as a mobile Hotspot and provides internet service to a client device which may have only a WLAN access. In another smartphone mobile Hotspot example, the mobile broadband modem, the WLAN AP and the Application Processor may be integrated into a single IC as shown in FIG. 8.
An example of a mobile broadband network is the Long Term Evolution (LTE) from the 3rd Generation Partnership Project (3GPP). The LTE technology and its evolution are often referred to as fourth generation (4G) technologies. A client device may also use any of the previous generation technologies such as “2G”, “3G” from 3GPP or 3GPP2 and/or other standardization bodies. A client device may also use future generation technologies for mobile Hotspot and mobile networks. Different sources of internet are generically referred to as networks herein.
Often client devices may start getting internet service from a mobile Hotspot device and at some point may stop using the internet service from the mobile Hotspot device. However, generally there may be no explicit indication from the client devices to the WLAN AP that they no longer need the service. The mobile Hotspot device may continue to broadcast the WLAN signals such as the beacon signal even when none of the client devices in its coverage area are requiring internet service or even when there is no client device present in its coverage area. Furthermore, the mobile Hotspot device may continue to perform the required operations such as receiving paging messages, receiving periodic broadcast messages, measurements on serving and neighbor cells, cell change, routing area updates, etc. for the connectivity with the mobile network using the WWAN modem even though there is no client device requiring any service on the WLAN AP.